The invention relates to sealing strips, and more particularly to channel-shaped sealing strips such as having a longitudinal channel-shaped gripping portion for supporting the sealing strip in position on the frame of an opening which is closable such as by a window or a door and, optionally, a longitudinal sealing portion on and running along the gripping portion. An exemplary field of application of the invention is in vehicle body construction.
It is known to construct such sealing strips by covering a relatively flexible channel-shaped metal carrier with elastomeric material. A problem which has to be overcome is a tendency of moisture to travel around the flange by passing inside the channel and over the flange edge--between the latter and the base of the channel. It is known to provide the opposite facing side walls of the channel with gripping ribs running longitudinally along the channel engaging and sealing against the sides of the flanges, but these do not necessarily completely overcome the problem.
It is also known to provide a layer of mastic material in the base of the channel for sealing against the edge of the flange. However, this has disadvantages because a special operation is necessary to place the mastic in position and it may deteriorate (lose its sealing properties) during storage or in use.
It is therefore an object of the invention to provide an improved channel-shaped sealing strip.
A more specific object of the invention is to provide an improved channel-shaped sealing strip which provides a more satisfactory seal between the edge of the flange in use and the base of the channel.
In a known form of channel-shaped sealing strip such as referred to above--that is, a channel-shaped sealing strip having internal gripping ribs extending longitudinally along opposite inside facing walls of the channel, it is also known to provide a sealing part running along the outside of one wall of the channel, this sealing part being positioned so as to seal against a door, for example, which closes the opening. A problem which can arise here is that the different parts of such a sealing strip have to perform different purposes, and it has been found that, in order to do this, they should not necessarily all be of the same consistency and/or hardness.
It is therefore a further object of the invention to provide a channel-shaped sealing strip in which the different parts are better adapted to suit their respective purposes but at the same time ensuring simplicity and economy in manufacture.